Getting your gears shifting quickly and smoothly should be quite an easy job to
do, but it takes a little bit of knowledge about how that system works first.
A clean, well-lubed chain will make a big difference to how easily that chain shifts
up and down that block, so do that first. Both front and rear mech work
on the system of having the correct cable tension so both your upshifts
and downshifts are quick. So let's break that down to three
parts. First your cables, then we'll look at the limit
adjusters. Then we'll actually look at the cable tension. So, first
thing to look at is the actual condition of your cables. If they're worn with loads
of friction in them, you'll never get those gears to work very well. So, what
I do, is I'll feel for it on the shifter. If there's a lot of friction when you're
pushing through that shifter, that's a sign that you've got a lot of friction
in there, or if it's a bit slow going down the block, that means the cable's
not returning nicely with the spring on your mech. If there is any friction
in there, now is the time to stick a new inner cable in, if not the whole
system. If the outers are kinked, you'll never get them working nice and smoothly
either, so that's when I just replace the whole gear, cable in it and outer.
So, going down to the rear mech, let's just have a quick look to make sure that
that mech is nice and straight, also that your rear hanger isn't bent.
So if you look down that cage, it should be absolutely parallel to your cassette,
you know, and nice and square to that back wheel. If that's still twisted or pulled
out, that pretty means that you've bent that hanger. That's going to affect your
shifting as well, so make sure that's straight first. I've undone that pinch
bolt that holds the cable into that rear mech, so now, pedaling the bike forward,
just push that mech up and towards the rear wheel and then let it go,
and that mech should return nice and quickly. If there's a bit of friction in
that mech as it drops back down, that's a sign that that mech might be a little bit
damaged or bent, so that's not going to help your shifting either.
So now let's look at the limit screws. Bear in mind that these don't affect the
actual shifting of the rear mech, they just limit how far it moves up and down.
So if you have that limit screw not set tight enough, that's when your mech can go
too far and go into that rear wheel, so that's something to pay attention to.
And the high and low works just like a car, so a high gear is fast speeds,
low is slow speeds. So that's your low gear and that's your high gear,
and you'll have a high and a low limiting screw on that rear mech.
So if we start with the high adjuster, remember to leave that cable unattached.
And as I'm pedaling the bike forward, you can see the chain is actually trying to
jump off the bottom tooth on my cassette, which means that this is mech is too far
outboard. If I give that mech a little push, now you can see it runs nice and
sweetly. So, I need to wind that high adjuster in clockwise slightly until I get
that chain running nicely on there. It's not trying to pull it off the bottom of
the cassette. On SRAM, the high adjuster, confusingly enough, is the other side.
So I'll stick half a turn on there, and see how that runs. Still wants a little
bit more, so another half turn. There we go. Give that mech a push,
let it drop back down. If you wind it too far on, you'll notice your chain won't
come nicely down into the easiest gear, so you want to take a little bit back off,
just so your chain comes into that gear, but no further.
Okay, so now we're going to look at the low speed up at the top of the cassette.
Like I said before, that's going to stop me from over-shifting and pushing that
mech into that rear wheel. You can also get that if it's not adjusted correctly,
maybe on a big landing or a big hit on the bike, the mech can jump.
If you've not got that adjuster set properly, that mech can jump into that
rear wheel, snap your mech, snap your hanger, and do some damage to that rear
wheel. So make sure this one's set nice and tight so the mech can't go too far.
So, pedaling the bike, I'm just going to push that mech up towards that top,
and as you can see, mine is going too far. That chain's jumped over the back of the
cassette and going into that back wheel, so I need to stick some adjustment,
wind that low adjuster clockwise in to limit that mech a little bit more.
Okay, so I've put a couple of turns on that low adjuster, pushed the mech up.
By now you can see it's not quite moving far enough, so I've put too much on that
low adjuster. So I need to back it off half a turn to make sure that chain goes
all the way up, but no further. There we go. Okay, so now the mech is
set up so you're getting the full range of gears, and it's
going no further. Now I'm going to put the cable back on,
and I'll double check those again once the cable's back on. Okay, so,
finally, we're going to look at the cable tension to get those gears working nicely.
So, with your cables still unattached from the rear mech, let's go up to the shifter
and just set this adjuster so it's clockwise all the way into the shifter,
and then go back out one turn. So, you've got a bit of adjustment both out and in,
to just give those final adjustments of tension on that cable.
So, make sure your shifter is down into the highest gear, so I'm all the way to
the bottom of the block. Now, I'm just going to pull ever so gently on that cable
to give it a little bit of tension, before I then tighten this bolt. So
now, we've mounted the cable through the rear mech, all the final adjustments come
from this barrel adjuster up on the shifter. So, let's have a run through the
gears. I'm pushing to go up to my lowest gears, and I've given it a push,
and it's not actually moved the chain up. That means I need to wind this adjuster
anti-clockwise, to put some more tension on that cable. Okay, so I'm going to give
that barrel adjuster half a turn anti-clockwise to put more tension on
that cable. Still not quite doing it, so let's give it a little bit more.
Try again, there we go. It's going up and into that lower gear.
It's still a little bit slow, so I'm going to put a little bit more tension on,
maybe a quarter of a turn. Try again. There we go, nice and
quick on those shifts towards the lower gears.
So, let's now check the shifts back down the block. If you put too much tension on
that cable, yes, your shift's going to the lower gears might be quick,
but that's going to maybe slow down the ones coming down the block. So let's
double check that. See how it's a little bit slow coming back down? That means
I've got a bit too much tension on that cable, so I'm going to give that barrel
adjuster half a turn back clockwise, take some tension off, and that's better.
So now, we can see we're getting quick shifts both ways, which means that that
tension's set nicely. I will double check those stop adjusters by shifting it up
right to the top, nice and quick, and make sure it doesn't go over the back of the
cassette, and then fire it down to the high gears, and then make sure that that
chain, again, doesn't jump off the bottom. Just remember that you do need a nice,
clean, gear cable in there. If there's any friction in that cable,
you might get the gears working one way nicely, but probably not the other way.
So there you go, there's setting up your gears. It's quite a simple process,
really. Big one is just definitely make sure you get those stop adjusters right,
so you don't risk any damage to your back wheel, or an expensive one where you rip
out the mech and do loads of damage, so get that sorted. If you found this video
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